I've just wasted some hours trying to get a script to execute. It threw an error saying that the 'object wasn't valid' I decided to give up, wen't home, and later at home started up again to see if I could sort it out.

It executed well on the first run.

Same computer. No changes to the script. ESTK was set to InDesign 5, I checked it a million times.

What could cause this to happen? Caches overflowing? "Blocks" between InDesign and ESTK? The script isn't callng for any URIs or such.